In our English class a student and a teacher are having a discussion about the expression "fancy doing sth". One of them says this phrase is old-fashioned and out-dated. The other says it is still in use. We're learning British English at school. Who is right? Can you help out? Thank you!

I don't know about British English, but people still use that phrase in the U.S., though rarely. In my opinion it sounds more upper-class! When I ask "Fancy a drink?" or say "She fancies him" it feels reminiscent of Jane Austen or the Victorian era. So old-fashioned, but also a little nostalgic.